/* ═══════════════════════════════════════════════
   SAMRIDDHA GANGULY — ACADEMIC PORTFOLIO
   Shared Stylesheet
   ═══════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Cormorant+Garamond:ital,wght@0,300;0,400;0,500;0,600;1,300;1,400;1,600&family=DM+Mono:wght@300;400;500&family=DM+Sans:ital,wght@0,300;0,400;0,500;1,300&display=swap');

/* ── TOKENS ── */
:root {
  --bg:         #04080f;   /* near-black navy */
  --bg2:        #070d1a;   /* cards */
  --bg3:        #0a1120;   /* section contrast */
  --surface:    #0d1628;   /* surfaces */
  --border:     rgba(100,140,200,0.09);  /* blue-tinted border */
  --accent:     #c8a96e;   /* gold — unchanged */
  --accent2:    #7b9ea8;   /* steel blue — unchanged */
  --accent3:    #a07bb5;   /* violet — unchanged */
  --text:       #e8e4dc;   /* unchanged */
  --text-muted: #7a7f90;   /* very slightly blue-shifted */
  --text-dim:   #3a3f52;   /* blue-shifted dim */
  --serif: 'Cormorant Garamond', Georgia, serif;
  --mono:  'DM Mono', monospace;
  --sans:  'DM Sans', sans-serif;
  --nav-h: 68px;
  --max-w: 1200px;
  --pad:   clamp(24px, 5vw, 80px);
}
/* ── LIGHT MODE ── */
body.light {
--bg:      #ffffff;   /* near-white, just a breath of warmth */
--bg2:     #fdfcfa;   /* cards — almost pure white */
--bg3:     #f2efe9;   /* subtle contrast */
--surface: #ffffff;
  --border:     rgba(139,111,61,0.22);
  --text:       #1a1816;
  --text-muted: #5f5a52;
  --text-dim:   #8a847a;
--accent:  #4169e1;   /* deep fountain pen blue */
--accent2: #4a7c96;   /* slate blue-grey */
--accent3: #6b4f8a;   /* muted violet */
  --accent-soft: #e8dcc6;
}
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth;}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-weight: 300;
  line-height: 1.7;
  overflow-x: hidden;
  min-height: 100vh;
}

/* Noise overlay */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='1'/%3E%3C/svg%3E");
  opacity: 0.025;
  pointer-events: none;
  z-index: 9999;
}

/* Scrollbar */
::-webkit-scrollbar { width: 3px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--accent); }

/* ── NAVIGATION ── */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--pad);
  border-bottom: 1px solid var(--border);
  background: rgba(10,10,15,0.9);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
}
.theme-toggle {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  padding: 0.35rem 0.8rem;
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
  cursor: pointer;
  transition: all 0.25s;
}

.theme-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
}
.nav-logo {
  font-family: var(--serif);
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--text);
  text-decoration: none;
  letter-spacing: 0.02em;
  flex-shrink: 0;
}
.nav-logo span { color: var(--accent); }

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  font-family: var(--mono);
  font-size: 0.68rem;
  font-weight: 400;
  color: var(--text-muted);
  text-decoration: none;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  transition: color 0.2s;
  position: relative;
}
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -3px; left: 0;
  width: 0; height: 1px;
  background: var(--accent);
  transition: width 0.3s;
}
.nav-links a:hover,
.nav-links a.active { color: var(--accent); }
.nav-links a:hover::after,
.nav-links a.active::after { width: 100%; }

.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 4px;
}
.nav-hamburger span {
  display: block;
  width: 22px; height: 1px;
  background: var(--text-muted);
  transition: all 0.3s;
}

/* ── PAGE HEADER ── */
.page-header {
  padding-top: calc(var(--nav-h) + 6rem);
  padding-bottom: 5rem;
  padding-left: var(--pad);
  padding-right: var(--pad);
  position: relative;
  overflow: hidden;
}
.page-header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}
.page-eyebrow {
  font-family: var(--mono);
  font-size: 0.68rem;
  color: var(--accent);
  letter-spacing: 0.25em;
  text-transform: uppercase;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  opacity: 0;
  animation: fadeUp 0.7s 0.1s forwards;
}
.page-eyebrow::before {
  content: '';
  width: 30px; height: 1px;
  background: var(--accent);
  opacity: 0.5;
}
.page-title {
  font-family: var(--serif);
  font-size: clamp(2.8rem, 6vw, 5rem);
  font-weight: 300;
  line-height: 1.05;
  margin-bottom: 1.5rem;
  opacity: 0;
  animation: fadeUp 0.7s 0.25s forwards;
}
.page-title em { font-style: italic; color: var(--accent); }
.page-subtitle {
  font-size: 0.95rem;
  color: var(--text-muted);
  max-width: 580px;
  line-height: 1.8;
  opacity: 0;
  animation: fadeUp 0.7s 0.4s forwards;
}

/* ── SECTION UTILITIES ── */
.section {
  padding: clamp(60px, 10vw, 100px) var(--pad);
}
.section-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  min-width: 0;
}
.section-label {
  font-family: var(--mono);
  font-size: 0.65rem;
  color: var(--accent);
  letter-spacing: 0.25em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}
.section-label::after {
  content: '';
  width: 40px; height: 1px;
  background: var(--accent);
  opacity: 0.4;
}
.section-heading {
  font-family: var(--serif);
  font-size: clamp(1.8rem, 3.5vw, 2.8rem);
  font-weight: 300;
  line-height: 1.15;
  margin-bottom: 3rem;
}
.section-heading em { font-style: italic; color: var(--accent); }
body.light nav {
  background: rgba(246, 241, 232, 0.92); /* matches --bg in light */
}
/* ── BUTTONS ── */
.btn-primary {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 0.85rem 2rem;
  background: var(--accent);
  color: var(--bg);
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.25s;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}
.btn-primary:hover { background: #d4b880; transform: translateY(-2px); }

.btn-outline {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 0.85rem 2rem;
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border);
  cursor: pointer;
  text-decoration: none;
  transition: all 0.25s;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}
.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-2px);
}

/* ── TAGS ── */
.tag {
  font-family: var(--mono);
  font-size: 0.63rem;
  letter-spacing: 0.08em;
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--border);
  color: var(--text-muted);
  transition: all 0.2s;
}
.tag:hover { border-color: var(--accent); color: var(--accent); }

/* ── FOOTER ── */
footer {
  border-top: 1px solid var(--border);
  padding: 3rem var(--pad);
  background: var(--bg);
}
.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  flex-wrap: wrap;
}
.footer-logo {
  font-family: var(--serif);
  font-size: 1rem;
  color: var(--text-muted);
  text-decoration: none;
}
.footer-logo span { color: var(--accent); }
.footer-copy {
  font-family: var(--mono);
  font-size: 0.65rem;
  color: var(--text-dim);
  letter-spacing: 0.08em;
}
.footer-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}
.footer-links a {
  font-family: var(--mono);
  font-size: 0.63rem;
  color: var(--text-dim);
  text-decoration: none;
  letter-spacing: 0.08em;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--accent); }

/* ── TIMELINE ── */
.timeline { position: relative; padding-left: 2rem; }
.timeline::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 1px;
  background: linear-gradient(to bottom, var(--accent), transparent);
}
.tl-item {
  position: relative;
  padding: 0 0 2.5rem 2rem;
}
.tl-item::before {
  content: '';
  position: absolute;
  left: -4px; top: 7px;
  width: 9px; height: 9px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg);
}
.tl-date {
  font-family: var(--mono);
  font-size: 0.65rem;
  color: var(--accent);
  letter-spacing: 0.12em;
  margin-bottom: 0.4rem;
}
.tl-title {
  font-family: var(--serif);
  font-size: 1.1rem;
  font-weight: 400;
  margin-bottom: 0.15rem;
}
.tl-place {
  font-size: 0.82rem;
  color: var(--accent2);
  margin-bottom: 0.5rem;
}
.tl-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.75;
}

/* ── CARD ── */
.card {
  background: var(--bg2);
  border: 1px solid var(--border);
  padding: 2rem;
  transition: border-color 0.25s, transform 0.25s;
  position: relative;
  overflow: hidden;
}
.card::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 1px;
  background: linear-gradient(to right, var(--accent), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s;
}
.card:hover { border-color: rgba(200,169,110,0.25); transform: translateY(-3px); }
.card:hover::before { transform: scaleX(1); }

/* ── ANIMATIONS ── */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}
@keyframes scrollPulse {
  0%, 100% { opacity: 0.4; transform: scaleY(1); }
  50%       { opacity: 1;   transform: scaleY(1.1); }
}

/* ── SCROLL REVEAL ── */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s, transform 0.7s;
}
.reveal.visible {
  opacity: 1;
  transform: none;
}

/* ── BG DECORATIONS ── */
.bg-blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  pointer-events: none;
}
/* Make entries clickable cards */
.cv-entry {
  display: block;
  text-decoration: none;
  color: inherit;
  padding: 1.5rem 1.75rem;
  border: 1px solid var(--border);
  background: var(--bg2);
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
  position: relative;
}

/* Lift + subtle glow */
.cv-entry:hover {
  transform: translateY(-5px);
  border-color: rgba(200,169,110,0.25);
  box-shadow: 0 10px 30px rgba(0,0,0,0.4);
}

/* Optional top accent line (matches your design language) */
.cv-entry::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 1px;
  background: linear-gradient(to right, var(--accent), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.cv-entry:hover::before {
  transform: scaleX(1);
}
/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-hamburger { display: flex; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: var(--nav-h); left: 0; right: 0;
    background: var(--bg);      
    border-bottom: 1px solid var(--border);
    padding: 1.5rem var(--pad) 2rem;
    gap: 1.25rem;
  }
}